In 1972, a Mainichi Shimbun journalist, Takichi Nishiyama, was prosecuted for disclosing a secret Japan-U.S. agreement whereby Japan would shoulder $4 million of the expenses for the transfer of Okinawa back to Japanese sovereignty. The government insisted there was no secret agreement.

Four million dollars was not a large amount — disclosed U.S. records have since shown secret agreements for more than $200 million. But even after the text of the $4 million agreement was released by the U.S. under its statuary 25 year declassification rule, Tokyo continued to insist there were no secret agreements. But how can you prosecute someone for disclosing a document you say does not exist?

In 2006 the declassified document was shown on television together with former Gaimusho North Americas Bureau chief Bunroku Yoshino, whose signature lay at the bottom. Earlier when serving in the Gaimusho Yoshino had denied the existence of the agreement. But in retirement he was quite happy to appear before the public agreeing that the signature shown on the document was indeed his own. Yet questioned in the Diet, Shinzo Abe, then chief Cabinet secretary, continued to insist that the document did not exist.